Nanomaterials are synthesized in a nanometer (109 m) scale to have new characteristics and exhibit unique properties for each material. Nanomaterials have been applied to materials industry, energy environment industry, electronics industry, machinery industry, and medical industry. Accordingly, it is expected to create convergence industries converging with existing industries and new nanotechnology markets. With the rapid development of nanotechnology and possibility to chemically synthesize magnetic nanoparticles, magnetic nanoparticles have merged with various fusion fields and have been used in magnetic memories, magnetic sensors, live cell separation, and the like. As magnetic, optical, and electrical characteristics may be adjusted by controlling size, crystallinity, arrangement, and the like of nanoparticles, adjustment of various characteristics is being studied according to application fields.
In particular, iron oxide nanoparticles have various phases such as Wustite (Fe1-xO), Hematite α-Fe2O3), Maghemite (γ-Fe2O3), and magnetite (Fe3O4). Iron oxide nanoparticles have applicability in various fields such as a magnetic resonance imaging contrast agent, a magnetic memory device, collection of contaminants, magnetic separation and cell arrangement, drug delivery, and the like due to unique characteristics thereof. To apply materials to various fields, it is essential to understand magnetic, electrical, and optical characteristics of the materials. Studies have been actively conducted on characteristic evaluation analysis of each type of iron oxide phases.
A magnetite-PMMA (poly(methyl methacrylate)) composite has been mainly used in thermo-sensitive drug delivery and cell separation systems. PMMA is a well-known polymer which may perform structural modification using thermal stimulus and electron irradiation. However, there is substantially no study which is conducted on properties of the magnetite-PMMA composite using light irradiation.
Moreover, it is not easy to predict a change in characteristics of the magnetic nanoparticles themselves and a changes in surrounding environment caused by a catalytic reaction to photo-thermal and photo-chemical reactions arising from a photoreaction. Accordingly, there is difficulty in synthesizing a composite fused with nano-sized iron oxide nanoparticles and preparing a new material induced by photoreaction.
According to an example embodiment, photothermal effect of iron oxide nanoparticles is induced by irradiating a high-power high-energy laser to Maghemite or magnetite-based iron oxide nanoparticles chemically synthesized in a reducing atmosphere of iron oxide using a specific polymer and a specific solvent, and deformation of a conjugated polymer type backbone chain of a neighboring polymer of the iron oxide nanoparticles is induced by generated heat. As a result, a white fluorescence nanoparticle polymer fluorescent composite is prepared.